May 13, 2008
New York Times

New Advice for Surgery on the Knees

By TARA PARKER-POPE

For years, people with worn-out knees were told to wait as long as possible before opting for replacement. Wait until you are older, the thinking went, so the joint will outlive you.

But medical experts say doctors and patients are pushing the limits of their old joints too far. Improvements in artificial joint technology and surgical techniques mean replacements are lasting longer than ever — often 20 years or more. But doctors are still advising candidates for replacement to "wait until you can’t stand it." As a result, some patients wait until the cartilage in their knees wears out completely, leaving them housebound and with painful bone-on-bone rubbing in their knees.

The problem is that patients who wait too long become so debilitated that recovery is harder and function is often not fully regained. “There’s definitely a point where there’s a diminishing return if you wait too long,” said Lynn Snyder-Mackler, a professor in the department of physical therapy at the University of Delaware. “You end up trading one set of impairments for another.”

About one in five adults has arthritis or chronic joint pain. As people age, cartilage begins to wear, and the resulting inflammation causes swelling, pain and stiffness. Jobs and sports that involve repetitive motion on a particular joint can increase the risk of developing arthritis in that joint. Family history and weight gain also play a role.

Joint replacement is not inevitable once arthritis sets in. Treating the pain and inflammation early on can help people maintain function longer. Over-the-counter and prescription pain relievers as well as supplements like glucosamine and chondroitin may offer relief. Maintaining a healthy weight lowers risk for arthritis in the knees. Moderate exercise can also help.

As for surgery, women appear more likely than men to wait too long before opting for it. It may be that they are more inclined to accept the limits of weakened knees. Doctors may discourage women from surgery because they typically live longer than men.

In research published last fall in The Journal of Bone and Joint Surgery, Dr. Snyder-Mackler and colleagues studied 95 men and 126 women who were to have knee replacements. They found that even after controlling for gender differences in strength and agility, the women had far higher levels of impairment before choosing surgery than the men had.

And earlier this year, The Canadian Medical Association Journal reported that doctors recommended surgery more often for men than for women. University of Toronto researchers selected one man and one woman, both 67, who had identical levels of knee osteoarthritis. They each went on separate visits to 29 orthopedic surgeons and 38 family doctors. Although they both described similar symptoms, two-thirds of the doctors recommended knee replacement for the man, while only a third thought it appropriate for the woman.

After years of suffering, Craig Mason, 65, of Whittier, Calif., insisted that her doctor refer her for a knee replacement. Ms. Mason could get around only using a walker. She said that when she was “truly incapacitated,” her doctor still wanted her to postpone surgery.

"My primary physician kept putting it off and putting it off, and finally I almost had to threaten and say, You’ve got to do something about this," she said. “He just wanted me to get older."

Last year, Ms. Mason underwent surgery. Recovery was painful, she said. But unlike the chronic pain associated with her knee, the pain of surgery and physical therapy eventually disappeared. “When I woke up from surgery I said, This was a big mistake,” she said. “But they say it’s like childbirth — you forget the pain. I should have had it done a long time ago.”

Total knee replacements are not for everyone, and doctors say patients in their 40s and 50s may still want to consider partial knee replacements or other interim surgical procedures.

Sometimes patients themselves insist on delaying surgery because they worry about long recoveries and giving up favorite activities that they now suffer through with braces and medication. Doctors say, however, that many patients can resume normal activities, although it depends on the person's fitness and disability levels before the surgery.